Radius dresser for grinding wheels



March 1944- F. s. BELLINGER 2,343,949

RADIUS DRESSER FOR GRINDING WHEELS Filed Feb. 18, 1941 5 Sheets-Sheet 1 7 I INVEIYTOR.

March 14, 1944. s BELUNGER 2,343,949

RADIUS DRESSER FOR GRINDING WHEELS Filed Feb. 18, 1941 5 Sheets-Sheet 2 Jan/"A442 S March 14, 1944. F. s. BELLINGER 2,343,949

RADIUS DRESSER FOR GRINDING WHEELS Filed Feb. 18, 1941 5 Sheets-Sheet 5 lNV ENT OR.

March 14, 1944. F. s. BELLINGER 2,343,949

RADIUS DRESSER FOR GRINDING WHEELS Filed Feb. 18, 1941 5 Sheets-Sheet 4 Fig.8

INVENTOR.

March 14, 1944- F. s. BELLINGER RADIUS DRESSER FOR GRINDING WHEELS Filed Feb. 18, 1941 5 Sheets-Sheet 5 INVENT OR.

,9 T TOP/YE) Patented Mar. 14, 1944 UNITED STATES PATENT OFFICE 4 Claims.

The object of my invention is to produce a special forming tool forkshaping the cutting edge of surface grinding wheels to various desired designs.

Another object is to provide a radius dresser for surface grinding wheels capable of forming either concave or convex surfaces thereon, or may be adapted for cutting angular surfaces on th wheel edge, or any desired combination thereof.

A further object is to produce a radius dresser for grinding wheels that is simple in construction, easily and elhciently operated and that can be manufactured at a low cost.

These several objects are attained in the pre-- ferred form by the construction and arrangement of parts more fully hereinafter set forth.

Similar parts on all drawings are marked by similar numerals or letters.

Fig. 1 is an elevation of the radius dresser showing the central support frame and the rotatable members as mounted thereon.

Fig. 2 is a top view of the assembled device showing the relative position of the various operating parts.

Fig. 3 is an end view of the dresser head showing the adjustable tool mountings as lowered to a position below the center of rotation set for cutting convex surfaces on a grinding wheel edge.

Fig. 4is a cross-sectional view as taken on the line 4-4 of'the Fig. 1 showing the adjustable control stops mounted on the back side of the head dial.

Fig. 5 is a cross-sectional view taken on the line 55 of the Fig. 1, showing the arbor clamps for locking the device in various set positions.

Fig. 6 is an end view similar to the Fig. 3, i1- lustrating the cutting tool raised to a position above the center of rotation as set for cutting concave surfaces on grinding wheel edges.

Fig. '7 is a similar end view of the dresser head, but with the supporting dial assembly rotated to a predetermined angular position, set for cutting beveled surfaces on grinding wheel edges.

Fig. 8 is a cross-sectional view of the dial head, taken on the line 8-8 of the Fig. 4, showing the adjustable stop means mounted thereon for determining the arc of rotation for any desired setting.

Fig. 9 illustrates my device attached to a grinding machine.

I will now describe more fully the detailed construction of my device, referring to the drawings and the marks thereon.

The base frame A is made of suitable metal,

and preferably formed of a rectangular base plate I with suitable end mounts 2 and 3 rigidly attached to the opposite baseends. at right angles thereto. A horizontal drive shaft 4 is rotatably mounted through suitable bearings provided in the end mounts 2 and 3, and positioned parallel with the base section I. Special rotary bearings 5 may be provided if desired. A small hand wheel 6 is fixedly mounted on one end of the shaft 4, roviding means for limited rotations of the unit. A dial head 1 is mounted on the opposite end of the drive shaft 4, and is rotatable therewith. The dial head I is provided with circumferential graduations a ranging from zero to ninety degrees in both directions and on opposite sides of the dial edge, the zero marks being positioned diametrically opposite each other. A zero indicator arm 8 is mouhted above the dial head 1 and securely attached to the upper end of the frame end mount 3, positioned in vertical alignment with the shaft axis. The inner face I) of the dial head I is provided with a circular flanged recess groove 9 positioned concentric with the axis of rotation, and carries two adjustable stop blocks l0 slidably mounted therein. The stop blocks l0 may be securely clamped within the dial groove at desired positions, by means of the internally mounted set screws H. An adjustable stop pin I2 is slidably mounted through the upper portion of the frame end mount 3, positioned in alignment opposite the dial groove 9, and engageable with the stop blocks II! when adjusted within the path of rotation. Across the outer face of the dial head i is mounted a horizontal flanged slide member l3 securely attached thereto by special countersunk screws l4, said slide being positioned in exact alignment with the oppositely positioned ninety degree graduation marks on the dial head circumference. A grooved slide block I5 is slidably mounted over the horizontal slide l3, positioned at right angles thereto and adjustable thereon. The slide block 15 is retained in a true central position of the dial 1 by means of special stop pins l6 mounted in the slide l3, although slidable thereon in either direction when the pins l8 are removed. The slide block I5 is formed with a flanged vertical slide l1 ositioned at right angles to the slide l3 and in exact parallel alignment with the opposite zero graduation marks as formed on the dial circumference. A special tool support slide block I8 is slidably mounted over the vertical slide I! and carries an extendedv tool arm I9 rigidly mounted therein by means of an adjustable clamp block 20 and operating set screw 2|. The tool arm I9 is provided with a diamond cutting point e fixedly mounted in the outer end thereof and positioned exactly in vertical'alignment through the axis of rotation so as to be moved to intersect therewith. The tool support slide .block I! may be adjusted to any desired position along the slide l1, and fixedly clamped thereto by the set screw 22 and connected clamp block 23. The outer ends of the slide block I are accurately milled to a predetermined dimension from the centerline of rotation, and carries at one end thereof an extended gage arm 24 fixedly attached thereto by the set screw 25. The gage arm 24 is positioned directly beneath and parallel to the tool arm l9, opposite the cutting point e, and is designed for accurately setting the tool point e exactly on the center of rotation, or offset therefrom, by placing an accurate gage block 26 therebetween. Any ofi'set may be made in either direction, above or below the center of rotation, and securely clamped in any position. The gage. arm 24 is attachable to either end of the slide block l5, and is removable therefrom as soon as the cutting point e and supporting arm l9 are accurately set for the desired radius cutting. The tool arm I9 is formed with symmetrically positioned angular surfaces d and e designed for fitting within corresponding angular walls formed within the supporting tool slide block l8, and can be mounted therein facing either direction as may be required for either concave or convex cutting.

In using my device for cutting special edge designs on grinding wheel faces, or on other typ s of abrasive cutting wheels, the tool arm l9 and cutting point e are first set in their required positions, above or below the center of rotation, and

depending upon the curve radius required to be formed in the wheel edge. The dial head I is then set at the zero graduation point, and the stops I 0 set at their proper positions to deter.- mine the exact length of the curved section to be formed when engaged with the stop pin I2. The assembled dresser unit is then rigidly mounted on a suitable grinding machine table, as illustrated in Fig. 9, preferably by a magnetic chuck if available, or any other suitable means for rigidly and securely retaining the dresser unit in position thereon, the dresser unit being adjusted on the machine table X so the extended tool arm I! and cutting point c is directly beneath the surface grinding wheel Y to be reformed, and in parallel alignment therewith. The cutting point e is to engage the wheel Y at the relative position desired for the concave or convex curve to be formed therein. As the grinding machine table Z and the attached dresser unit B is raised so that the grindin -wheel Y engages the tool cutting point e when the grinding wheel is in rotation, the drive shaft 4 is oscillated in both directions by means of the hand wheel 6, and the oscillations continued between the stops I0 as the dresser unit B is raised, and the proper depth curve is formed on the wheel edge. When the cutting tool point c is positioned below the center of rotation, a convex edge is formed-on the wheel surface, and-when the pointc is raised above the center of rotation a concave wheel edge is formed. The exact size of the curve-depends upon the radius ofiset provided in either case.

When an angular surface is desired-formed on the grinding wheel edge, the dial head I is rotated to'the desired angle as determined by the graduations a, and the shaft 4 locked in position by the threaded clamp wheel 28 and engaging clamp members 29. As the grinder table x and attached dresser unit B is raised so as to contact the cutting point c with the wheel edge, the stop pins [6 are both removed, and the slide block ll slowly displaced along its supporting slide I2, continuing the movement manually, back and forth as the cutting point e is raised against the wheel edge and until the full grinding wheel Y is properly faced.

By various adjustments and operations, any desired combination of curves and faces may be formed on the wheel.

It is apparent that my radius dresser is subject to various modifications in both arrangement of parts and sections as well as in detail construction without departing from the spirit of my invention.

Having fully described my radius dresser for grinding wheels, what I claim as my invention and desire to secure by Letters Patent is:

l. A grinding wheel dressing device designed for forming various designs on said wheel edges, comprising a rigid support frame suitable for fixedly mounting on a grinding machine table, a horizontal drive shaft rotatably mounted through said support frame and provided with turning means at one end thereof, a dial head fixedly mounted on the opposite shaft end at right angles thereto and rotatable therewith, shaft locking .means mounted on said support frame engageable with the drive shaft, said dial head being graduated on ach quarter from zero to ninety degrees in each direction, arranged with their respective zero marks diametrically opposite each other, a support slide fixedly mounted across the outer dial head face and at right angles to the axis of rotation, positioned in alignment with the opposite ninety degree graduation marks, a symmetrical slide block with secondary slide mounted on said support slide and positioned at right angles thereto and in direct alignment with the oppositely positioned zero graduation marks, detachable pin means mounted in the support slide for retaining said slide block and secondary slide in a central position intersecting the axis of rotation, an adjustable tool block mounted on secondary slide and provided with means for locking same in adjusted positions thereon, a tool arm with cutting point attached fixedly mounted in said tool block projected therefrom in parallel alignment with the drive shaft, a gage block mounted on one, end of the secondary slide for retaining a gage unit for setting the tool point with respect to the axis of rotation, and stop members mounted on the dial head for limiting the angular rotation of the unit.

2. A dresser for fashioning grinder wheels comprising a rigid support frame including a base plate adapted to be fixedly mounted on the table of a grinding machine in predetermined relation to the path of the grinder wheel, a rotary shaft mounted in said frame with its axis parallel to the plane of said base plate and table being also in the plane of rotation of said grinder wheel, a head secured to one end of said shaft, a pair of stop members relatively angularly adjustable upon said head about the axis of said shaft, a stop member on said frame cooperating with the aforesaid stop members to limit the rotary adjustment of said head and shaft, a second head adjustable on said first head in a plane perpendicular to the axis of saidshaft and upon opposite sides of said axis, means for normally locking said second head in its central position, a third head transversely adjustable on said second head to various degrees of eccentricity and upon opposite sides of the axis, an arm projecting from said third head, and a trimming point mounted on said arm and located in the grinding plane of said grinder wheel whereby the dressing of the grinder wheel is performed in the same plane as the grinding operation.

3. A dresser for fashioning grinder wheels to a predetermined cross sectional contour, comprising a rigid support frame including a base plate adapted to be fixedly mounted on a table of a grinding machine in predetermined relation to the path of the grinder wheel relative thereto, a rotary shaft mounted in said frame with its axis parallel to the plane of said base plate and table and also in the plane of rotation of said grinder wheel, a head secured to one end of said shaft to be rotatable therewith, means for limiting the arc of rotation of said head, means for locking said shaft at a limit of rotation thereof, a second head adjustable on said first head in a plane perpendicular to the axis of said shaft and upon opposite sides of said axis, means for normally locking said second head in its central position, a third head transversely adjustable on said second head to various degrees of eccentricity and upon opposite sides of the axis of said shaft, an arm projecting from said third head, and a trimming point mounted on said arm and located in the grinding plane whereby said grinder wheel may be dressed to a contour including arcuate and tangent straight line portions and said dressing is performed in the same plane as-the grinding operation.

4. A dresser for fashioning grinder wheels to a predetermined cross sectional contour comprising a rigid support frame including a base plate adapted to be fixedly mounted on a table of a grinding machine in predetermined relation to the path of the grinder wheel relative thereto, a rotary shaft mounted in spaced bearings on said frame with its axis parallel to the plane of said base plate and table and also in the plane of rotation of said grinder wheel, means at one end of said shaft for rotating the same, a head secured to the opposite end of said shaft, means for limiting the arc of rotation of said head, means between said bearings for locking said shaft from rotation, a second head adjustable on said first head in a plane perpendicular to the axis of said shaft and upon opposite sides of said axis, means for normally locking said second head in its cen tral position, a third head transversely adjustable on said second head to various degrees of eccentricity and upon opposite sides of the axis of said shaft, an arm projecting from said third head, and a trimming point mounted on said arm and located in the grinding plane of said grinder wheel whereby the dressing of said grinder wheel is performed in substantially the same plane as the grinding operation to obtain exact correspondence between the dressed contour and the ground contour in the work.

FRANKLIN S. BELLINGER. 

